During the experience you'll hear music from the L.A. Phil, find a secret homeless encampment, and meet the aforementioned cat-person, played by actress Jena Malone.

We took the tour. Here's how it unfolds.

IT BEGINS WITH AUGMENTED-ISH REALITY

You strap on an iPad Mini and put on headphones. Cardiff's voice offers ruminations on everything from music to human connectedness, while guiding you in a calming fashion into the parking garage, up stairs, into alcoves, into elevators, onto high walkways, and even into the concert hall itself.

It's not what's usually meant by augmented reality, even though that's what the L.A. Phil is promoting it as — it's actually a 40-minute film shot along the route you'll be guided on. You're instructed to hold up the iPad Mini and match what you see on your screen to your surroundings.

"It's about this overlapping of realities — it's about the past and present aligning or something, that for me, has this magic point," Miller said.

Cardiff and Miller call it "physical cinema," because it's a movie where you're in the same space the film was shot. They also described it as cheap virtual/augmented reality.

You can get a better idea of what it's like by looking at video from one of their previous walks here:

CREATING THE DISCONNECT IN YOUR BRAIN

Cardiff and Miller have been producing these video walks since around 1999 or 2000, they said. Cardiff was producing audio walks even sooner — 1991 — starting with cassette tapes before moving to CDs, then iPods, and now iPad Minis.

The physical spaces are the same, but you'll see events unfolding on screen — a fight, a wedding, workers doing modern dance, a weird cat person played by Jena Malone that dances around and sneaks up on you — that differ from what's actually happening. The headphones are also playing what's known as binaural sound, which make you feel like sounds are coming from all around you.

"We like the dislocation between how the brain copes with what they see [on the screen] and what they see out there," Cardiff said.

Miller explained that he records that sound by walking around with microphones in his ears, along with added foley work in post.

The combination creates a weird disconnect in your brain, in your perceptions, as you try to separate what's on screen from what's really happening.

Malone, who you might know from movies like the Hunger Games series, was already a fan of Cardiff and Miller. She was brought on to play another character, but then they lost the actor set to play the cat character.

"He went off for another film, and Jena said, 'Well you know what, I really am interested in the cat character.' So we said, 'Sure, you can be both, because he has a mask!'" Cardiff said.

The way Malone moved as the cat, combined with the way that she looked at you through the mask, gave the character a real intensity, according to Cardiff.

THREE-DIMENSIONAL WRITING

The video starts you on a bench near the front entrance. Early on, you meet a character who thinks she's a cat, wearing an unsettling cat mask.

"It's like three-dimensional writing. Because some [narration] lines just don't work in some situations," Cardiff said.

The video works with time jumps, putting you into areas at different times of year, in different types of weather. The disorientation of the experience works in tandem with science fiction elements, including references from Philip K. Dick's "The Preserving Machine" to Schrödinger's cat, tying in with the cat-person character.

The L.A. Phil, as seen in video walk Thought Experiments in F# Minor at Disney Hall. (Courtesy L.A. Phil)

You'll come across the L.A. Phil playing virtually for you in multiple locations around the hall, in both rehearsal and performance settings. The work includes original music by composer Ellen Reid, inspired by the Philip K. Dick story.

"We picked the idea of a Bach fugue, F-sharp minor, was a bug, that went into the machine," Cardiff said. "And then it came out, and it turned into Ellen's music."

Reid riffed on that idea to create her piece.

"There are all these themes in the piece I wrote that are from the fugue," Reid said. "So all of the fast strings writing is directly, basically a different rhythm of the fugue melody."

She also re-harmonized the fugue melody to make it sound more modern. The music was also inspired by the harshness of the modern world, but as the world can be beautiful in parts, the music was too, according to Cardiff.

As high tech as what Cardiff and Miller do is, they aren't particularly interested in other forms of augmented reality, with a walk that tracks your phone's movements. It's up to you to track the walk, trying to keep up and synchronize your view with the movements on screen.

"We like to keep it simple," Miller said. "We were like, but the camera — it does that all without having any big computers that you need."

HOW YOU CAN SEE IT

You can go to Disney Hall and take the 40-minute video walk between 10 a.m. and 2 p.m. on most days, for free. It's the same hours that self-guided audio tours are offered. This one probably won't teach you much, but will blow your mind.

Watch video from their one experiment with augmented reality here, conecting sounds with locations in a hallway: